Cediranib Maleate in Treating Patients With Relapsed, Refractory, or Untreated Acute Myeloid Leukemia or High-Risk Myelodysplastic Syndrome

Inclusion Criteria: * Histologically or cytologically confirmed acute myeloid leukemia (AML) ormyelodysplastic syndromes meeting 1 of the following criteria: * Relapsed AML meeting any of the following criteria: * Good-risk cytogenetics (inv\[16\], t\[8;21\], or t\[15;17\]) in second orgreater relapse * Patients with AML t(15;17) must have failed prior tretinoin and arsenic-containing regimens AND progressed orrelapsed within 12 months of therapy * In first or greater relapse * Resistant AML * Unable to achieve first complete remission after at least 2 inductionregimens * Untreated AML meeting any of the following criteria: * At least 60 years of age * Preceding MDS * MDS * International Prognosis Scoring System (IPSS) risk groupof intermediate-2 or higher * Patients with relapsed disease after allogeneic hematopoietic stem cell transplantation (HSCT) must be off allimmunosuppressive medications for at least 30 days and have no symptoms orsigns of graft-vs-host disease * No active CNS metastasis * Patients with clinical signs of CNS disease or a history of CNS diseasewithin the past 6 months are required to undergo lumbar puncture to excludeCNS involvement * No symptomatic leukostasis or requirement for leukapheresis * Not eligible for allogeneic HSCTAND no suitable donor at the time of study entry * Patients who areeligible for HSCT, informed of the option, and choose not to proceed to HSCTare allowed * ECOG performance status (PS) 0-2 OR Karnofsky PS 60-100% * Bilirubin normal * AST and/or ALT ≤ 2.5 times upper limit of normal * Creatinine normal OR creatinine clearance ≥ 60 mL/min * No proteinuria ≥ 1+ on 2 consecutive urinalysis taken ≥ 1 week apart * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * No HIV positivity * LVEF ≥ 45% by echocardiography * Mean QTc ≤ 500 msec (with Bazett's correction) * No other significant ECG abnormality * No history of familial long QT syndrome * No disseminated intravascular coagulation * No history of allergic reactions attributed to compounds of similar chemical orbiological composition to AZD2171 * No concurrent uncontrolled illness, including, but not limited to, any of the following: * Hypertension * Thyroid disease * Ongoing or active infection * Symptomatic congestive heartfailure * Unstable angina pectoris * Cardiac arrhythmia * NYHA class III-IV heart disease * NYHA class II heart disease controlled with treatment allowed * Psychiatric illness or social situations that would limit study compliance * See Disease Characteristics * More than 4 weeks since prior chemotherapy (6 weeks fornitrosoureas or mitomycin C), radiotherapy, or major surgery and recovered * Hydroxyurea allowed to control peripheral blast count\> 20,000/mcL prior to study entry and during the first 3 days of study therapy * More than 4 weeks since prior and no concurrent growth factor or other cytokine support * At least 30 days since prior investigational agents or participation in aninvestigational trial * No more than 3 prior courses of induction chemotherapy * Induction chemotherapyis defined as that intended to induce complete remission and given at a time thatthe patient has active disease * No concurrent CYP interactive medications * No other concurrent investigational agents * No concurrent drugs or biologics with proarrhythmic potential * Prior and concurrent hydroxyurea allowed to control peripheral blast count\> 20,000/mcL during the first 3 days of study therapy